The present invention relates generally to hoof protection, and more particularly to shoes for hoofed animals such as horses, ponies, mules, cattle, and the like.
Horses have been shod with metal shoes held in place by nails since the advent of the Iron Age. Horse shoeing was necessary to protect and support the hoof while horses engaged in activities beyond their natural ability due to the softness of their feet. Since horses hooves are uniquely shaped, iron offered several advantages. Iron is easily shaped, and may be affixed to the hoof with metal nails to accommodate a horse""s individual needs. Also, iron protects the hoof from chipping and increases the sole""s distance from the ground. In addition to these advantages, the shape of the horseshoe effectively increases the weight bearing surface area of the hoof, which, in turn, increases a horse""s stability.
Today""s domestic horse is faced with very different challenges than those encountered in nature, such as the presence of slippery road surfaces and the need to engage in high-performance sports. While steel shoes offer a horse a high degree of protection and support, they have many shortcomings. First, steel shoes generally lack traction on hard surfaces, and are poor shock absorbers. Second, steel shoes are too heavy for certain horses and may cause problems such as interference with limb motion. Third, steel shoes generally require installation by a person possessing specialized skills such as a professional farrier. Fourth, nails present an inherent risk of injury due to misplacement in the hoof. Fifth, horseshoes may be shaped incorrectly and may alter the horse""s natural movement and cause damage over time. Sixth, use of the wrong size of shoe may lead to a host of hoof and leg ailments. Finally, all shoes affixed with nails run the risk of being thrown with devastating results if the shoe is ripped from the hoof, injuring both the hoof wall and the limb. Over time, attempts have been made to address these problems with varying degrees of success.
Aluminum horseshoes help to solve the issues of traction, shock absorption, weight, and, to a lesser extent, support. Aluminum shoes are made in three basic varieties, racehorse shoes, orthopedic shoes, and therapeutic shoes. However, aluminum shoes have several shortcomings, including short useful life and high cost.
Equine boots, such as those provided in U.S. Pat. Nos. 5,692,569; 5,588,288; 5,528,885; 4,174,754; 3,732,929; and 3,703,209 provide various examples of alternative devices that address the issues of traction and shock absorption without the use of traditional horseshoes. Some of the general characteristics common to these devices are as follows. They are designed to provide for easy installation, and are primarily utilized to provide a temporary solution for a missing or thrown shoe. They fit over the hoof, and are generally made from solid rubber, or other synthetic material with tread on the sole portion. While useful temporarily, these devices are typically heavy and clumsy, and substantially detract from a horse""s performance. In some cases, the added weight of these devices causes interference between the horse""s limbs. Additionally, the typically awkward shape of these devices makes them difficult for riders to carry, despite the fact that carrying them as a field-based horseshoe replacement is one of principal reasons they are purchased. Equine boots also tighten around the hoof with closures that can be clogged, damaged or broken by rocks, debris, or rugged terrain. In addition to excessive weight and clumsy design, these devices also tend to rub the bulbs of the hoof heels. This may cause sensitivity, bleeding and lameness in the heel area, rendering the horse unusable. Equine boots come in a variety of sizes but in only one standard shape, making them extremely difficult to install and to properly conform to hooves that differ from the standard design. To address this flaw, silicone inserts and adhesives are used to keep some of these devices affixed to the hoof making them extremely difficult to remove. The materials typically used in equine boots make it difficult for horse owners to modify them.
To avoid the need for nails, glue-on shoes have also been developed, which attach to the hoof through the use of tabs that are affixed to the hoof wall. There are generally two varieties of glue-on shoes. The first variety includes shoes fabricated from plastic, polyurethane, or other synthetic material that cannot be shaped to accommodate the unique shape of a horse""s hoof. Some glue-on shoes of this variety, however, are made from softer materials that bend against the wall of the hoof, but which fail to conform to the wall""s shape. This design absorbs impact, provides some traction, and eliminates the issues surrounding nailed shoes. However, the tabs of these devices are easily scraped from the wall when the horse negotiates uneven terrain or encounters deep footing. Additionally, soft glue-on shoes typically lack adequate support, as they fail to conform properly to the hoof wall. Another drawback of glue-on shoes is that they must be installed by a person having special skills such as a farrier, and are thus costly and inconvenient to install. The second type of glue-on shoe is similar to the first, except that it contains a soft metal core, typically aluminum. This addition was intended to allow unique shaping on an anvil or other bending apparatus. This customization is difficult because the hammer tends to bounce off the outer material during the shaping process, with little or no change to the core. As a result, a shaper must strike harder, resulting in an increased chance of damaging the outer material during the shaping process. Because of the design, sharp bends are difficult, if not impossible, to accomplish.
Polyurethane or synthetic shoes are affixed to the hoof with nails. They address issues related to shock absorption, traction and support. These devices have a standard shape and cannot be adequately fashioned to accommodate unique hoof shapes. This results in shoe material extending beyond a horse""s normal support surface, increasing the risk of horseshoe loss resulting from snagging. Polyurethane or synthetic shoe varieties sometimes include a metal core help to solve this problem by allowing for size alteration via grinding. However, if the metal core becomes exposed, the shoe""s effective life decreases substantially.
Synthetic shoes come in a variety of styles (including bar shoes, bar shoes with clips, open shoes, and open shoes with clips) and sizes, but are not easily adaptable to the unique shape and size of an individual horse""s hoofs. These devices also have the disadvantages associated with nails such as lameness due to nail misplacement, tearing of the hoof wall when the shoe is thrown, and the necessity of professional installation.
Hard facing and screw-in caulks were developed as further attempts to adapt steel shoes to situations where horses require traction. Hard facing is a method by which a farrier or skilled professional spreads expensive high carbon metal chips (typically barium or titanium) contained in an adhesive flux over a horseshoe""s impact points. This extends the life of the shoe and increases traction on hard surfaces. The primary problem with hard facing is localized shock. Over time the areas hoof that are beneath the hard facing begin to delaminate. This increases the chance of abscesses, seedy toe, white line disease, and Laminitis. Screw-in caulks have been employed for centuries, as a method wherein a farrier taps a desired numbered of holes in a shaped horseshoe depending on the activity the horse is performing. The shoes are then nailed to the hoof and the threaded holes are sealed with cotton, beeswax rubber, or other closure. When necessary, the owner may remove the closure and screw the caulk into the shoe with a caulk wrench or other tool. Problems exist with sealing the threaded holes as closures fall out or wear out, and are not replaced. Furthermore, debris tends to fill the holes, making caulks difficult to install. Cross threading and caulk selection are problems, as horse owners may choose inappropriate devices for their horse""s activity. While this device, when functioning properly, is effective for achieving traction, it may cause injury to an animal""s joints, tendons, and ligaments.
Horseshoe pads as exemplified in U.S. Pat. No. 5,199,498; rim pads as exemplified in U.S. Pat. No. 4,565,250; and therapeutic pads as exemplified in U.S. Pat. No. 4,775,011 are used to reduce shock, prevent bruising and address therapeutic issues such as ring bone, side bone, Laminitis, navicular disease, tendon and ligament sprains, coffin bone and navicular bone fractures, splints, as well as other hoof and limb injuries or aliments. Horseshoe pads are affixed between the hoof and shoe and are available in many varieties, which generally fit into the three categories mentioned above: full pads, rim pads, and therapeutic pads. Full pads cover the plantar surface of a horse""s hoof completely. Rim pads cover only the area of the hoof that comes in contact with the shoe. This open center allows the bottom of the hoof to grab in deep footing and soft surfaces. The open center also makes cleaning of the hoof easier. Therapeutic pads come in many shapes and cover the entire hoof or portions of it. Design choices may result in redirected or reduced pressure, changed balance, and protection for certain structures. Current horseshoe pads suffer from several drawbacks. The thickness of the pad weakens the connection between the shoe and the hoof by placing stress on the thinner portion of the nails used to affix shoe and pad to the hoof. Also, full pads tend to cause the hoof to harbor bacteria. Hoof packing is used to combat this effect. However, eventually the packing gets pushed out, and bacteria incubate causing problems such as abscesses, thrush, seedy toe, and white line disease. Furthermore, full pads can cause an anvil-like effect against the sole of the hoof, mitigating the intended effect when the sole is not properly prepared or when the wrong packing is used.
Therefore, it is an object of the present invention to overcome the problems just discussed, and to provide a protective device for hoofed animals which is preferably fabricated from a resilient and elastic material, and which is adaptable to a variety of hoof sizes.
A protective device for hoofed and shod animals is presented including a body portion 105 having, a base portion 106 formed in an approximately ring-like or U-shaped fashion around a central opening 212; a wall portion 108 formed on the base portion 106 and extending upward and inward at an angle toward the central opening 212; a sole portion 210 extending inward toward the central opening 212, such that it is customized to fit over a hoof of a shod animal and forms a support surface for the hoof upon application of the device, said sole portion 210 including a ground surface 118 on the bottom of the base portion 106 to provide a walking surface when the device is applied; and a means for size adjustment 216 formed in the body in order to allow for adjustment to varying hoof sizes; and a means for detachably attaching the body portion 105 to a hoof of a bare or shod animal, whereby a hoof may be placed in the body portion 105 and held in place by a combination of the base portion 106, the wall portion 108, and the means for detachably attaching the body portion 105, and such that the device conforms substantially with the circumference of a hoof. Furthermore, the means for attaching the sole portion of the base portion to a hoof of a bare or shod animal includes at least one hole 316 to provide for attachment by an attachment means. Attachments means which may be used with the present invention include nails, screws, and caulks and the like. Also, the base portion 106 is preferably made from a harder, more rigid material and the wall portion 108 is made from a softer, more pliable material. By forming the base portion 106 of a harder, more rigid material, it is made more durable and it is also more supportive of the horse, whereas with a softer material the varying compression of the material due to irregularities in the weight distribution across the hoof may lead to balance problems for the horse. Also, in cases where a device is conformed for the use of a specific type of shoe, e.g. a horseshoe, the rigidity of the base portion 106 may aid in ensuring that no slippage of the shoe with respect to the base portion 106 may occur. On the other hand, forming the wall portion 108 of a softer, more pliable material, allows the present invention to be more easily applied over a hoof. It may be advantageous to utilize a material having a somewhat xe2x80x9cstickyxe2x80x9d character to help it adhere to the hoof, thereby providing a better grip with the hoof. Furthermore, the softer, more pliable material also assists in ensuring a fit that is much more snug than would be available using a harder, more rigid material for this purpose.
Additionally, the base portion 106 may be designed to include a rolled edge 120 formed circumferentially around at least a portion thereof, and adjoining the ground surface 118 of the sole portion 210 in order to prevent the device from catching against the ground as steps are taken. Additionally, the means for detachably attaching the body portion 105 to a hoof may provide a circumferential closure causing the device to conform to a hoof. In other words, the device may be formed as a continuous piece of material that xe2x80x9cslipsxe2x80x9d onto the hoof. In another embodiment, the means for detachably attaching the body portion 105 to a hoof may include a strap 112 having a plurality of holes 114, a plurality of pegs 116 formed on the wall 108 of the body portion 105, and a sizing opening 214 in the body 105, whereby the device may be placed on a hoof, and the sizing opening 214 adjusted through use of the strap 112, and held fixed on the hoof by the plurality of holes 114 and pegs 116. A wide variety of closure mechanisms may be provided to allow for detachable attachment of the device. In addition to forming the device in a continuous ring-shape and as a U-shape with a strap, various other attachment mechanisms may be used, non-limiting examples of which include clips, buckles, and Velcro.
The sole portion 210 may also include a tread bevel 306, formed in the ground surface 118 and extending inwardly and upwardly toward the central opening 212 of the device in order to prevent debris accumulation between the sole portion 118 and an animal""s hoof as well as in the central opening 212. In another embodiment, the ground surface 118 of the sole portion 210 may include a plurality of tread grooves 304 in communication with the central opening 212, and extending radially from the central opening 212, with the tread grooves 304 formed to allow for adjustment of the device around a hoof. The device may be, fabricated by the process of injection molding. In another embodiment, the base portion 106 of the device 104 may include a vertical thickness, which may be variable for different sections of the base portion 106 to assist in correcting for an animal""s particular needs. In another embodiment, the body portion 105 may include a shear-relief portion 302 at the intersection of the wall portion 108 and the base portion 106, said shear-relief portion 302 opening roughly toward the central opening 212. The device may further be custom-fitted to a particular horse in order to ensure optimal fit.